It was being billed by the government yesterday as the largest ever cash boost to the national health service and for once, even the independent experts agreed the spin doctors had given the real doctors something to cheer about.

After enduring two years of belt tightening in the aftermath of Labour's election, the NHS will enjoy above inflation increases of 6.1% a year on average over the next four years - twice the historical average. And unlike the last time the chancellor announced a boost for health spending, the treasury number crunchers cannot be accused of using creative accounting techniques to grab the headlines.

Independent statisticians at the Institute of Fiscal Studies last night vetted the chancellor's figures and agreed this was the most generous increase in spending since at least 1979 - as far back as their analysis goes. For most of the NHS's more than 50 year existence, spending has risen by just 3.3% above in inflation.

The IFS said yesterday's boost would bring Britain's health spending up to the European Union average by 2004, meeting the prime minister's pledge on television this year.

However, at 8% of national income, it will still be below the spending levels achieved in France and Germany where health takes 9.6% and 10.7% of GDP.

And if spending rises in the rest of Europe over the next four years, the average will also rise, moving the goal posts for Mr Blair's pledge.

By the end of the period, spending on the NHS will have grown from £49.3bn a year, to £68.7bn - a 50% increase in cash terms, and a 35% increase once the likely effect of inflation is taken into account.

But to achieve this unprecedented increase, the chancellor has torn up his three year spending programme for the public sector announced in July 1998. Under the original plans laid out in the first comprehensive spending review, NHS spending was set to rise on average at 4.7% a year be tween April 1999 and March 2002 - above the historical average but below the 5.4% average the Tories achieved between 1989 and 1993.

Instead, the NHS bonanza will begin this April, in what should have been the second year of the comprehensive spending review. The promised £52.2bn - already a £2.9bn increase on the previous year - has now been boosted by an extra £2bn.

"If spent right it will deal with some of the major problems faced by the health service," a spokesman for the King's Fund said. Even the doctors were enthusiastic. Ian Bogle, chairman of the British Medical Association, said: "We are delighted that the government has responded so quickly to our call for a fundamental review of health service funding. We see this as a first major step to putting the health service on a firm, long term basis."

The health secretary, Alan Milburn promised that the new four year settlement would provide a platform for modernisation.

But the IFS cautioned that people had high expectations of the government on health, and had already been disappointed once.